title: Qualitative and quantitative real time myocardial contrast echocardiography for detecting hibernating myocardium.
abstract: BACKGROUND
  Real time myocardial contrast echocardiography (RTMCE) is an emerging imaging modality for assessing myocardial perfusion that allows for noninvasive quantification of regional myocardial blood flow (MBF).
  
  
  OBJECTIVE
  We sought to assess the value of qualitative analysis of myocardial perfusion and quantitative assessment of myocardial blood flow (MBF) by RTMCE for predicting regional function recovery in patients with ischemic heart disease who underwent coronary artery bypass grafting (CABG).
  
  
  METHODS
  Twenty-four patients with coronary disease and left ventricular systolic dysfunction (ejection fraction <45%) underwent RTMCE before and 3 months after CABG. RTMCE was performed using continuous intravenous infusion of commercially available contrast agent with low mechanical index power modulation imaging. Viability was defined by qualitative assessment of myocardial perfusion as homogenous opacification at rest in ≥2 segments of anterior or ≥1 segment of posterior territory. Viability by quantitative assessment of MBF was determined by receiver-operating characteristics curve analysis.
  
  
  RESULTS
  Regional function recovery was observed in 74% of territories considered viable by qualitative analysis of myocardial perfusion and 40% of nonviable (P = 0.03). Sensitivity, specificity, positive and negative predictive values of qualitative RTMCE for detecting regional function recovery were 74%, 60%, 77%, and 56%, respectively. Cutoff value of MBF for predicting regional function recovery was 1.76 (AUC = 0.77; 95% CI = 0.62-0.92). MBF obtained by RTMCE had sensitivity of 91%, specificity of 50%, positive predictive value of 75%, and negative predictive value of 78%.
  
  
  CONCLUSIONS
  Qualitative and quantitative RTMCE provide good accuracy for predicting regional function recovery after CABG. Determination of MBF increases the sensitivity for detecting hibernating myocardium.
authors.affiliation: Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil Fleury Group, São Paulo, Brazil.
authors.forename: Daniela Ribeiro Aleixo
authors.initials: DR
authors.lastname: Fernandes
authors.forename: Jeane Mike
authors.initials: JM
authors.lastname: Tsutsui
authors.forename: Edimar Alcides
authors.initials: EA
authors.lastname: Bocchi
authors.forename: Luiz Antônio Machado
authors.initials: LA
authors.lastname: César
authors.forename: João César Nunes
authors.initials: JC
authors.lastname: Sbano
authors.forename: José Antonio Franchini
authors.initials: JA
authors.lastname: Ramires
authors.forename: Wilson
authors.initials: W
authors.lastname: Mathias
mesh_terms: D000465:Algorithms; D003199:Computer Systems; D003287:Contrast Media; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017682:Myocardial Stunning / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media